The 3Dkin program creates seperate files for each calculated parameter. Using the output name the file extention is identifying the type of parameter.
Calculated parameters assoiciated with file extention:
jml/jmr - Joint moment left/right leg
jfl/jfr - Joint force left/right leg
jal/jar - Joint angle left/right leg
lvl/lvr - Linear velocity left/right leg
lal/lar - Linear acceleration left/right leg
avl/avr - Angular velocity left/right leg
aal/aar - Angular acceleration left/right leg
eal/ear - Euler angle left/right leg
aml/amr - Angular momentum left/right leg
All files created with the 3Dkin program are text files, and can be open with fx. wordpad or any other text editor.
The following listing determine the row name in each parameter file.
Joint moment file (Extention: jmr/jml)(Units: Nm)
Joint force file (Extention: jfr/jfl) (Units: N)
Joint angle (Extention: jar/jal) (Units: deg)
Linear acceleration (Extention: lar/lal) (Units: m/s2)
Linear velocity (Extention: lvr/lvl) (Units: m/s)
Angular velocity (Extention: avr/avl) (Units: deg/s)
Angular acceleration (Extention: aar/aal) (Units: deg/s2)
Euler angle (Extention: ear/eal) (Units: rad)
Angular momentum (Extention: amr/aml)
Exporting or importing data
When the results has to be analysed or a presentation has to be created, the results can easely be imported into Excel, Sigmaplot or other graphing programs. All data file type is text files wich most graphing or statistical programs can import.
Vaughan, C.L. Davis, B.L. O'Conner, J.C. (1992) Dynamics of human gait. Human kinetics publishers. (Book)
Comments: This book is the basic of the 3Dkin program. But due to some error in the calculation in the euler angles this part has been modified.
Grood, E.S., Suntay, W.J., (1983) A joint coordinate system for the clinical description of three-dimensional motions: Application to the knee. Journal of Biomechanics Engineering, 105, 136-144.
Comments: This article give the background information on how the joint coordinate system (as a model) is created
Winter D. (1988) The Biomechanics of motor control and human gait. Waterloo: Waterloo Press.
Comments: This is a book on 2D but give a solid understanding on kinetics of human movement and many other aspects.
Kadaba, M.P., Ramakrishnan, H.K., Wootten, M.E. (1990) Measurement of lower extremity kinematics during level walking. Journal of Othhopaedic Research, 8, 383-392.
Comments: This is an article for 3D kinematics of lower extremity. In the article they use a different marker configuration called the Helen Hayes marker setup.
Verstrate, M.C., (1991) A technique for locating the center of mass and principal axes of the lower limb. Medicine and science in sports and exercise. Dec, 825-831.
Comments: This article explains a different technique for locating ridgid body CM and principal axes of the lower extremity than used in the 3Dkin program.
Tupling, S.J., Pierrynowski, M.R., (1987) Use of cardan angles to locate rigid bodies in three-dimensional space. Medical & Biological Engineering & Computing, 25, 527-532.
Comments: This article describes how a ridgid body can be located in 3D space, focusing on the issues of cardan/euler angles.
Three dimensional analysis of movement (1995)- Human kinetics publishers. (Book)
Comments: This book gives a detailed description of all aspects in 3D human movement.
Kadaba, M.P., Ramakrishnan, H.K., Wootten, M.E., Gainey, J., Gorton, G., Cochram, G.V.B. (1989) Repeatability of kinematic, kinetic and electromyographic data in normal adult gait. Journal of Othhopaedic Research, 8, 383-392.
Comments: This is an article evaluates the repeatability of lower extremity kinetics, kinematics and EMG.
In the search for literature the internet can provide a free search database. PubMed is a free medline literature database. Most common jurnals on biomechanical issues are included. Follow the link.